On 5.0.99.6;
#lang lazy
(define ones (cons 1 ones))
(define ints (cons 1 (map + ints ones)))
(+ (list-ref (take 15 ints) 1234)) 2) produces 1237
'take' doesn't produce a proper list (which has a 'null' in the end),
instead it produces a list with an element and a promise. When another
function needs to go on with the rest, it sees that promise and can
continue with that., instead of seeing a 'null' and produce an error.
That's a bug I think.
-- caner
p.s. With the same program, I got an error on 5.0.1
On 01/26/2011 10:40 AM, Mark Engelberg wrote:
> I get an error in 5.0.2, rather than 0.
>> --Mark
>> P.S. I was surprised to see that list-ref in #lang lazy takes the args
> in opposite order than in #lang racket (which takes the list first).
>> On Tue, Jan 25, 2011 at 11:27 PM, John Clements
> <clements at brinckerhoff.org <mailto:clements at brinckerhoff.org>> wrote:
>> I would expect this program to signal an error:
>> #lang lazy
>> (define zeros (cons 0 zeros))
>> (define should-be-error (list-ref (take 15 zeros) 1324))
>>> ... but instead should-be-error is bound to zero. How can I take
> the 1000th element of a list with only 15 elements? I'm tempted
> to make snide comments about laziness, but I'm sure it'll backfire
> when it turns out that somehow that's the right answer after all.
>> Bug report?
>> John
>
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